package cn.cj.erp.common.utils;

import cn.hutool.core.util.ArrayUtil;
import cn.hutool.core.util.ObjectUtil;
import cn.cj.erp.common.constants.HttpStatus;
import cn.cj.erp.common.http.Result;
import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/**
 * 客户端工具类
 *
 * @author chenjian
 */
@Slf4j
public class ServletUtils {
    /**
     * 获取String参数
     */
    public static String getParameter(String name) {
        return getRequest().getParameter(name);
    }

    /**
     * 获取String参数
     */
    public static String getParameter(String name, String defaultValue) {
        return Convert.toStr(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name) {
        return Convert.toInt(getRequest().getParameter(name));
    }

    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name, Integer defaultValue) {
        return Convert.toInt(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取Boolean参数
     */
    public static Boolean getParameterToBool(String name) {
        return Convert.toBool(getRequest().getParameter(name));
    }

    /**
     * 获取Boolean参数
     */
    public static Boolean getParameterToBool(String name, Boolean defaultValue) {
        return Convert.toBool(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获得所有请求参数
     *
     * @param request 请求对象{@link ServletRequest}
     * @return Map
     */
    public static Map<String, String[]> getParams(ServletRequest request) {
        final Map<String, String[]> map = request.getParameterMap();
        return Collections.unmodifiableMap(map);
    }

    /**
     * 获得所有请求参数
     *
     * @param request 请求对象{@link ServletRequest}
     * @return Map
     */
    public static Map<String, String> getParamMap(ServletRequest request) {
        Map<String, String> params = new HashMap<>();
        for (Map.Entry<String, String[]> entry : getParams(request).entrySet()) {
            params.put(entry.getKey(), ArrayUtil.join(entry.getValue(), ","));
        }
        return params;
    }

    /**
     * 获取request
     */
    public static HttpServletRequest getRequest() {
        return getRequestAttributes().getRequest();
    }

    /**
     * 获取response
     */
    public static HttpServletResponse getResponse() {
        return getRequestAttributes().getResponse();
    }

    /**
     * 获取session
     */
    public static HttpSession getSession() {
        return getRequest().getSession();
    }

    public static ServletRequestAttributes getRequestAttributes() {
        RequestAttributes attributes = RequestContextHolder.getRequestAttributes();
        return (ServletRequestAttributes) attributes;
    }


    /**
     * 将字符串渲染到客户端
     * @param string   待渲染的字符串
     */
    public static void renderStr(HttpServletResponse response, Integer httpStatus, String string) {
        try {
            if (ObjectUtil.isNull(httpStatus)) {
                response.setStatus(200);
            } else {
                response.setStatus(httpStatus);
            }
            response.setContentType("application/json");
            response.setCharacterEncoding("utf-8");
            response.getWriter().print(string);
        } catch (IOException e) {
            log.error("将字符串渲染到客户端异常\n", e);
        }
    }

    /**
     * 将字符串渲染到客户端
     * @param string   待渲染的字符串
     */
    public static void renderStr(HttpServletResponse response, String string) {
        ServletUtils.renderStr(response, HttpStatus.SUCCESS, string);
    }


    /**
     * 将字符串渲染到客户端
     * @param string   待渲染的字符串
     */
    public static void renderStr(String string) {
        ServletUtils.renderStr(ServletUtils.getResponse(), HttpStatus.SUCCESS, string);
    }


    /**
     * 将结果渲染到客户端
     * @param result   响应体
     */
    public static void renderResult(HttpServletResponse response, Result<?> result) {
        log.error("响应失败： {}", result);
        ServletUtils.renderStr(response, HttpStatus.SUCCESS, JSON.toJSONString(result));
    }

    /**
     * 将结果渲染到客户端
     * @param result 响应结果
     */
    public static void renderResult(Result<?> result) {
        ServletUtils.renderStr(ServletUtils.getResponse(), HttpStatus.SUCCESS, JSON.toJSONString(result));
    }

    /**
     * 是否是Ajax异步请求
     */
    public static boolean isAjaxRequest() {
        String accept = ServletUtils.getRequest().getHeader("accept");
        if (accept != null && accept.contains("application/json")) {
            return true;
        }

        String xRequestedWith = ServletUtils.getRequest().getHeader("X-Requested-With");
        if (xRequestedWith != null && xRequestedWith.contains("XMLHttpRequest")) {
            return true;
        }

        String uri = ServletUtils.getRequest().getRequestURI();
        if (StrUtil.equalsAnyIgnoreCase(uri, ".json", ".xml")) {
            return true;
        }

        String ajax = ServletUtils.getRequest().getParameter("__ajax");
        return StrUtil.equalsAnyIgnoreCase(ajax, "json", "xml");
    }

    /**
     * 内容编码
     *
     * @param str 内容
     * @return 编码后的内容
     */
    public static String urlEncode(String str) {
        try {
            return URLEncoder.encode(str, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            return StrUtil.EMPTY;
        }
    }

    /**
     * 内容解码
     *
     * @param str 内容
     * @return 解码后的内容
     */
    public static String urlDecode(String str) {
        try {
            return URLDecoder.decode(str, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            return StrUtil.EMPTY;
        }
    }
}
